Field of the Invention
The present invention relates to a vaporized fuel treating device used in a fuel feeding system for feeding fuel contained in a fuel tank to an engine. More particularly, the present invention relates to a vaporized fuel treating device used in a fuel feeding system for feeding fuel contained in a fuel tank to an engine and capable of detecting failures of a pressure sensor for detecting inner pressures of the fuel tank.
Description of Related Art
A failure detection device of a pressure sensor for detecting inner pressures of a fuel tank is taught by, for example, Japanese Laid-Open Patent Publication No. 5-195895. The failure detection device is attached to a vaporized fuel treating device that is used in a fuel feeding system for feeding fuel contained in the fuel tank to an engine. The failure detection device is configured to determine that the pressure sensor has failed when a change in detection values of the pressure sensor in a predetermined period of time after the engine is started is smaller than a predetermined value.
However, in the failure detection device of Japanese Laid-Open Patent Publication No. 5-195895, a failure detection procedure of the pressure sensor is performed only in a limited period of time after the engine is started. That is, when failures of the pressure sensor occur after the laps of this limited period of time, the failure detection cannot be performed until a next period of time after the engine is again started. Therefore, the failures of the pressure sensor cannot always be detected at an early time.
Thus, there is a need in the art for an improved vaporized fuel treating device used in a fuel feeding system for feeding fuel contained in a fuel tank to an engine and capable of detecting failures of a pressure sensor for detecting a pressure in the fuel tank.